[Gta04-owner] Host AP mode

[Dr. H. Nikolaus Schaller]

Am 30.05.2012 um 08:13 schrieb Christoph Mair:

> On Wed, May 30, 2012 at 12:13 AM, Butrus Damaskus
> <butrus.butrus at gmail.com> wrote:
>> On Tue, May 29, 2012 at 11:11 PM, Christoph Mair
>> <christoph.mair at gmail.com> wrote:
>>> On Tue, May 29, 2012 at 10:45 PM, Andreas Kemnade <andreas at kemnade.info> wrote:
>>>> Hi,
>>>> 
>>>> I found out that
>>>> http://corysohrakoff.wordpress.com/2011/09/13/enabling-wifi-ap-mode-on-a-gumstix-overo/
>>>> is a good howto about host ap mode.
>>>> It is about using an alternate driver for the wifi chipset (libertas_tf)
>>>> which uses a thinner firmware, so the host can do ap mode. I could
>>>> configure hostapd so that I have an unencrypted accesspoint.
>>>> The libertras_tf driver needs some
>>>> #include <linux/module.h> to work with 3.2 kernel. I have used hostapd
>>>> version 1.0.
>>>> Normal infrastructure mode does also work.
>>> 
>>> Great! The last time I gave it a try I could not connect to my
>>> network; scanning worked fine.
>>> 
>>>> But my earlier mentioned wifi performance problem with 3.x, which does
>>>> not exist in 2.6.32, is not better with the libertas_tf driver.
>>>> Could the SD/MMC host driver be the bottleneck?
>>> 
>>> I tried to debug the MMC interface and found out that the chip
>>> interface runs at 25MHz. I've read somewhere that the module should
>>> support up to 50MHz but I could not convince the module to use this
>>> speed. Anyways, 25MHz with a 4 bits wide interface should be enough
>>> for everyone [TM].
>>> 
>>> Unfortunately I could not find out why the chip does not use higher
>>> data rates than 5MBit/s. I've seen very short periods where iwconfig
>>> displayed higher data rates (up to 48MBits/s) but the value returned
>>> immediately to 5MBits/s when I called iwconfig again (a few times).
>> 
>> 
>> What is the signal strength/quality?
> 
> I can't remember exactly, but I also tested it standing next to the AP (2m).

I wonder if this is a single observation with Christoph's board (it was
one of the first that were produced) or a general issue. As far as I
followed this discussion, Andreas has high speed with the 2.6.32
kernel but not with 3.x.

Anyone else seeing this speed up/down effect?

BR,
Nikolaus